No, I would tell him that he can play for Brazil but that he will have to accept that his indiscipline in the derby means that plenty of people feel let down and frustrated that he is potentially further jeopardising his availability for the club. I would tell him that international football is important, is a great experience, and that I would support him playing in World Cup qualifiers, but he needs to learn from what's happened and ensure there is no repeat. But I would be clear: jetting off now, for all the right reasons, is not a good look when he's been unavailable due to his own actions. Go for it, but take any criticism as motivation to properly manage his emotions in stressful situations. Champions League clubs expect their players to be available as much as possible...
Basically, I am not against Richarlison playing for Brazil. But the frustration some feel is definitely on him. I think this needs to be made clear to him - and I am assuming it has been. It's possible to feel irritated by this state of affairs and at Richarlison's inability to hold his temper in a big game - a poor message to so-called "elite" clubs - while simultaneously supporting his wish to play World Cup games for his country - another iffy signal to the glamour boys. But he's a big boy, and he'll need to assume some responsibility if things go further awry in South America.
